Biogenic silica in intertidal marsh plants and associated sediments of the Yangtze Estuary

• Published in: Journal of environmental sciences (China) 2010, Vol.22 (3), p.374-380
• Main Authors: Hou, Lijun, Liu, Min, Yang, Yi, Ou, Dongni, Lin, Xiao, Chen, Hui
• Format: Article
• Language: English
• Subjects: biogenic silica; Geologic Sediments - chemistry; intertidal flat; marsh plants; Phragmites australis; Plants - chemistry; Plants - metabolism; Rivers - chemistry; Scirpus mariqueter; Silicon Dioxide - chemistry; Silicon Dioxide - metabolism; Spartina alterniflora; the Yangtze Estuary; Time Factors; Wetlands; 互花米草; 植物组织; 沉积物; 沼泽植物; 潮间带; 生物硅; 长江口
• ISSN: 1001-0742; 1878-7320
• DOI: 10.1016/S1001-0742(09)60118-2

Biogenic silica （BSi） contents in the marsh plants （Phragmites australis, Scirpus mariqueter and Spartina alterniflora） and associated sediments in Chongming Island eastern intertidal flat of the Yangtze Estuary were determined. The BSi contents in P. australis, S. mariqueter and S. alterniflora varied from 25.78–42.74 mg/g, 5.71–19.53 mg/g and 6.71–8.92 mg/g, respectively. Over the entire growth season, P. australis and S. mariqueter were characterized by linear accumulation patterns of BSi. The aboveground biomass （leaves and culms） of the marsh plants generally contained more BSi than underground biomass （roots）. BSi contents were relatively higher in dead plant tissues than in live tissues which was probably due to the decomposition and the leaching of labile components of plant tissues such as organic carbon and nitrogen. Comparing with the habitats of S. mariqueter and S. alterniflora, the highest BSi content was recorded in sediments inhabited by P. australis, with an annual average of 15.69 mg/g. Overall, the intertidal marshes in the Yangtze Estuary may act as a net sink of BSi via plant uptake and sedimentary burial.